1. Field of the Invention
The present invention relates to an accounting apparatus and method for a mobile communication system, and more particularly to an apparatus and method for generating an invoice for data having no error in a mobile communication system.
2. Description of the Related Art
Generally, a CDMA (Code Division Multiple Access) mobile communication system has been developed from typical voice-centered mobile communication standards to the next generation mobile communication standards to make it possible to transmit not only voice signals but also high-speed radio data. This next generation mobile communication standard called IMT-2000 (International Mobile Telecommunication-2000) is now being developed to bring a new age of a high-speed radio data service. Presently, a CDMA2000-1x (IS-95C) system supports a radio data communication service at a data transmission speed of 144 kbps corresponding to a speed double that of an IS-95B system. In the future, assuming that a CDMA2000-3x system is developed, a user may receive a communication service at a maximum speed of 384 kbps. There are various kinds of the communication services, that is, a VOD (Video On Demand) service, a music video service, a TV broadcasting service, etc. A user may receive service data over a packet network instead of a circuit network. In this case, the user may have to pay a charge for a total of quantity communication data (i.e., the number of packets) not total communication use time. Therefore, service providers have to provide the user with an accurate explanation of the charges by accurately indicating on their bill the quantity of communication data.
Presently, SK telecom Co., Ltd. and Korea Telecom Freetel Co., Ltd., which are representative service providers in the Republic of Korea, adopt a monthly fixed rate in their accounting system, and charge their subscribers a fee in excess of the monthly fixed rate based on a predetermined time zone such as a common time zone, a discount time zone, and a midnight time zone, as shown in the following TABLE 1.
TABLE 1MonthlyFixedOver Free Communication TimeClassificationRateFree Communication Time(Won per 10 seconds)Data——CommonDiscountMidnightStandardTimeTimeTimeZoneZoneZoneData 60270060 minutes17 won12 won8 wonwon(20 minutes/10 minutes/30 minutes)Data 1204500120 minutes17 won12 won8 wonwon(50 minutes/20 minutes/50 minutes)Data 2408500240 minutes17 won12 won8 wonwon(100 minutes/40 minutes/100 minutes)
As shown in the above TABLE 1, SK telecom Co., Ltd. and Korea Telecom Freetel Co., Ltd. charge their subscribers (i.e., users) a usage fee on the basis of the communication time irrespective of the used data quantity. As seen from the table, they have a scale of charges dependent only on the time zones such as common, discount, and midnight time zones. However, in recent times, they have announced a new accounting plan by which a usage fee for the next generation mobile communication system (e.g., 2G or CDMA2000-1x) is dependent on the quantity of data for various types of Internet content used, as shown in the following TABLE 2.
TABLE 2Contents TypeRate Base (1 packet = 512 bytes)E-mail (Text)6.5 won/packetCharacter Download6.5 won/packetNorahbang (Karaoke)2.5 won/packetMP32.5 won/packetDownload Game2.5 won/packetVOD2.5 won/packet
As shown in the above TABLE 2, subscribers are unchanged usage fees based on the quantity of the received data for each of Internet Contents. For example, the usage fee of 6.5 won per packet is applicable to the E-mail service, and another usage fee of 2.5 won per packet is applicable to the VOD service.
However, the above-mentioned accounting methods have a disadvantage in that data loss caused by a poor channel condition very frequently occurs while using a network such as the Internet. Accordingly, the user has to pay his or her usage fee even when poor data is received or data is lost from Internet Contents over the network such as the Internet.
Typically, in the case where a packet service is transmitted to a mobile communication terminal, data loss occurs in a PPP (Point-to-Point Protocol) layer, and further, more serious data loss occurs while the mobile communication terminal is moving. In this case, after the lost data is discarded, a data re-transmission procedure is performed in a TCP (Transmission Control Protocol) layer. However, according to the conventional accounting method, the service providers have undesirably charged their users for the lost data. In other words, the conventional accounting method has a disadvantage in that too much money is unfairly charged to the users when a large amount of data loss occurs due to a poor channel condition.
In the case where the user receives undesired data instead of his or her desired data over the network, the user must pay a usage fee for the undesired data to a corresponding service provider although there is no data loss in a data transmission procedure. In more detail, in the case where unnecessary data instead of necessary data to be received from a TCP/UDP (Transmission Control Protocol/User Datagram Protocol) service port number is transmitted to a user's terminal while the user uses an application program, it is desirable that a usage fee for the unnecessary data is not charged to the user. But, actually, the user must pay the service provider usage fee for the unnecessary data. Also, in case of an UDP, where unnecessary data is successively received from a server because a user's terminal is not released from the server after completing a user's application program, the user must again pay an excessive fee for the unnecessary data.